"Understand 50 Philosophical Classics in One Book" is a philosophy popularization work by the young Japanese philosophy scholar Hirano Taku. This book aims to help readers systematically absorb philosophical knowledge, rethink themselves, understand themselves, and understand the world. It selects 50 classic works of Western philosophy from ancient times, the Middle Ages, modern times to modern times, including "The Apology of Socrates", "The Republic", "The Prince", "Confessions" and "On Human Inequality". "The Origin", "Social Contract", "The Deathly Disease", "The Birth of Tragedy", "The Human Condition", "Melancholic Tropics", "Words and Objects"... The author gives a concise and clear summary and summary of the historical background and professional terminology of each work one by one, and analyzes the essence contained in them in detail, and attaches the author's explanation. Corresponding diagrams are also provided for explanation. As the author says, even a high school level can understand it. Once published, this book was very popular among Japanese readers. It was quickly reprinted many times after it was released. It has been printed 19 times, has sold more than 100,000 copies, and has been authorized in South Korea.